I agree, and I need to clean those drawings up so they are crystal clear to read and understand. Thanks for pointing out that there are dimensions to features on the back sides of parts. A big no-no, and it makes me cringe to see that I did that. On the parts that require an orthographic view of the rear side, some labeling of views would be helpful as well, to help distinguish front from rear. My apologies for the mis-drilled holes. I'll take some responsibility on that one.
There are very few pieces that need a perfectly square end. Again, this was intentional, as I was cutting everything by hand with a hacksaw. The most critical ones would be the nut plate block (part #27) and the four spacers (part #24). It would be nice to have the bearing blocks (parts #15, 17) as square as you can get them, but probably isn't the end of the world if they are off slightly.
On a related note, those 4 spacers can be replaced with a purchased part. I've been playing around with an upgrade to the 4 carriage studs (increasing them from 1/4" studs to 5/16" bolts) and I replaced the spacers with ones I purchased from
Quality Aluminum Spacers - Largest Selection on the Web. They are 11/16" in length, 5/8" o.d and 3/8" i.d, which works perfectly with the larger 5/16" bolts. The 11/16" length is .010" longer than the homemade spacers the plans currently call for, but there is plenty of built-in tolerance to absorb that small difference. They are nice and square and are only $1.20 each.
Glad to hear that progress is being made with the machine build. I also found that it was fastest to set up the drill press/vice and drill all of the similar holes across all the parts. I found it to be faster to do that than to keep switching drill bit size while working on one part. I just takes some good organizational skills to keep track of everything.
I'm actually in a similar position as you right now in choosing electronics. It seems that one of my stepper motors died. So I can either replace that one motor for $40, or take it as an omen that I should upgrade the whole system. I was in the middle of rewiring my limit switches when this happened, so it would be good timing if I want to switch drives. That Gecko 540 is very enticing indeed.
-Bob